You saw Stolas for the first time in her demon form which made you scared a little, Stolas was protecting you from Stella at the moment

She looks behind her and sees you sitting one the ground with your knees up to your chest. She gets on her knees and leans down to be on your eye lvl "Oh my dear, hey don't be scared. Please don't be scared she will never hurt you again darling." Stolas said in a soothing tone and she picks you up and holds you in her arms